Exploitation of deployed telecommunication fiber infrastructures for sensing applications

The optical fiber infrastructure deployed in our cities to support the metropolitan area networks is exploited for sensing applications, where the optical sensing signals co-propagate together with the telecom traffic. Thanks to a coherent interferometric approach, structural monitoring of buildings can be achieved in deployed passive optical networks based on fiber-to-the-home structure. Moreover, the same technology is experimented in urban fibre ring networks to detect and localize mechanical vibrations or dynamic perturbation

Vibration Sensing for Deployed Metropolitan Fiber Infrastructures

A counter-propagating coherent vibration sensing approach is exploited in a 32km deployed fiber ring network, proving its feasibility in early detection of critical events that may damage and put out of service the optical infrastructure

Vibration Sensing for Deployed Metropolitan Fiber Infrastructures

A counter-propagating coherent vibration sensing approach is exploited in a 32km deployed fiber ring network, proving its feasibility in early detection of critical events that may damage and put out of service the optical infrastructure

Structural vibration sensing in a deployed PON infrastructure

Deployed Passive Optical Network (PON) infrastructures are proved to potentially support remote structural vibration monitoring while simultaneously downstreaming 10Gbit NRZ transmission

Demonstration of structural vibration sensing in a deployed PON infrastructure

We demonstrate the possibility of using a deployed Passive Optical Network (PON) infrastructure for structural vibration monitoring for smart city applications and simultaneously downstream 10Gbit NRZ transmission. The impact of PON trunk fibre backscattering noise on sensing system performance is experimentally assessed

Testing ERT and fiber optic techniques at the laboratory scale to monitor river levees

In this paper we present the results of laboratory tests using electrical resistivity tomography (ERT) and fiber optic techniques to monitor river levees. A small-scale levee was constructed with the scale of 1:12 based on the earthen levee of an irrigation canal in San Giacomo delle Segnate, Italy, where a customized ERT monitoring system has been operating since September 2015. The most important mechanisms affecting the stability of river levees were simulated during different tests. To explore the possibility of using fiber optic sensors to monitor the integrity of levee structures, Fiber Bragg Grating (FBG) technology was adopted and four Organic Modified Ceramics (ORMOCER) coated 250\u3bcm-diameter fibers were deployed at the water exit side of two leakage zones. ERT data from a miniaturized electrode spread show that changes in the water level in river and the rainfall events significantly affect the resistivity distribution in the levee. Using TDR data, the relationship between water content and resistivity values was calibrated to be able to translate the inverted ERT images into water content maps. The results of fiber optic measurements showed the feasibility of fiber optic sensors to detect the deformations of the levee body in response to water infiltration